Zayas,R.G-D., Merino-Ibarra,M., Matos-Pupo,F. and Soto-Jimenez（最初のeの頭に´）,M.F.(2012): Atmospheric deposition of nitrogen to a Caribbean coastal zone (Cayo Coco, Cuba): Temporal trends and relative importance as a nitrogen source. Water Air Soil Pollut., 223, 1125-1136.

『カリブ海沿岸地帯（キューバ、カヨココ島）への窒素の大気沈着：時間トレンドと窒素源としての相対的重要性』

『Abstract
　Nitrogen (N) deposition to the ocean is thought to be increasing worldwide, but the amount of coastal and open ocean measurements is very limited. In this paper, we assess N deposition in the coastal zone of Cayo Coco, in central Cuba, during a multi-annual period (2005-2007). Wet and dry N depositions were estimated based on the NH4+ and NOx- concentrations in the rain. Cold fronts and troughs, coming from the west, contributed most to rain (41%) and to N deposition, followed by tropical waves and storms coming from the east, which caused 31% of the rain. Average concentrations of NH4+ and NOx- in the rain were 8.8 and 8.3μM. NOx- presented a clearly decreasing trend (0.26μM per month), decreasing by half during 2005-2007. Total N deposition averaged 3.23 kg N ha-1 year-1, similar to that found in Virgin Islands and Puerto Rico, but lower than previously measured in Cuba and in nearby areas of the USA and than model predictions for the oceanic region around Cuba. These low values and the decreasing trend found are attributed to drastic reduction of fossil fuel and fertilizer use in Cuba since 1990. Because land input has decreased even more drastically, deposition seems to be nowadays the most important N source to the coastal zone of Cayo Coco. The δ15N range of seagrass (Thalassia testudinum) and macroalgae (Penicillus dumetosus) in the area (1.83‰ to 3.02‰ and +1.02‰ to +4.17‰, respectively) sustain that atmospheric sources (deposition and N2 fication) comprise 70-90% of the N budget.

Keywords: Rainfall; Nutrient; Budget; Isotopic; nitrogen deposition; Seagrass』

1. Introduction
2. Methods
　2.1. Study area
　2.2. Rainfall, N concentrations, and deposition
　2.3. N budget for the coastal zone of Cayo Coco
　2.4. N isotopic composition of T. testudinum and Penicillus dumetosus
3. Results
　3.1. Rainfall and synoptic processes
　3.2. Nitrogen concentrations in rainfall
　3.3. N deposition
　3.4. N budget for the coastal zone of Cayo Coco
　3.5. Nitrogen isotopic composition of T. testudinum and P. dumetosus
4. Discussion
5. Summary
Acknowledgments
References

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